migration-startlisted

# Start a migration Begin a zero-downtime schema migration using pgroll. ## Usage ```bash xata roll start <migration-file.yaml> ``` ## Example ```bash # Start the migration (expand phase) xata roll start migrations/002_add_role.yaml # Test your changes with both old and new schemas running npm run dev # ... verify everything works ... # Complete the migration (contract phase) xata roll complete ``` ## How pgroll works pgroll uses an **expand-contract pattern**: ### Expand phase (`xata roll start`) - Creates new columns/tables - Sets up views for both old and new schemas - Installs triggers to keep both in sync - Both versions of your app work simultaneously ### Contract phase (`xata roll complete`) - Removes old schema views - Drops sync triggers - Cleans up ## Migration file format pgroll migrations are YAML files with declarative operations: ```yaml operations: - add_column: table: users column: name: role type: text nullable: false default: "'member'" ``` ## Common operations - `create_table` — Create a new table - `add_column` — Add a column to existing table - `drop_column` — Remove a column - `rename_column` — Rename a column - `alter_column` — Modify column properties - `create_index` — Add an index See [pgroll documentation](https://pgroll.com/docs/latest/operations) for all operations. ## Check migration status ```bash xata roll status ```